Leinster picked up the points against the Ospreys with a ponderous 18-11 Magners League victory in front of a small crowd at the Liberty Stadium.

Young fly-half Jonathan Sexton made the difference for the Heineken Cup champions, kicking five penalties in reply to a try to Ospreys blindside Jerry Collins. Collins also spent time in the sin-bin, along with prop Duncan Jones, as the home side plunged further in to the mire with back-to-back defeats.

Sexton kicked the opening points of the night after two minutes, capitalising on a penalty opportunity after the Ospreys were guilty of holding on. The early kicking exchanges were won by Sexton, but he blotted copybook by spilling a routine high-ball and presenting the home side with their first attacking platform.

Powered forward by two explosive runs from their props, the Ospreys were awarded their first penalty when Leinster strayed offside. James Hook, handed the No.10 jersey that he has set out to claim as his own, easily slotted the kick.

Another lengthy kicking duel yielded another chance for the visitors, when Hook failed to claim a spiralling kick. The onrushing Leinster pack forced first Jamie Nutbrown and then hooker Huw Bennett backwards, Bennett conceding a scrum under the posts. The Ospreys pack stood firm, winning a penalty as Leinster tight-head Stan Wright repeatedly slipped his bind.

Sexton landed his second penalty soon after, before a scything break by wing Nikki Walker brought the Liberty Stadium crowd to their feet. The Ospreys' support play was sub-par though and the opportunity fizzled out without an overlap being forged.

Leinster were guilty of similar profligacy when in sight of the Ospreys' line, working 9 phases through the forwards and ignoring a blatant overlap out wide. Debutant lock Nathan Hines, fresh from the British & Irish Lions tour, made the initial burst from a lineout but his fellow forwards were guilty of keeping the ball tight for too long.

The Ospreys picked up a turnover, Nutbrown clearing for Tommy Bowe to chase. Bowe put pressure on Shaun Berne, drawing a penalty which Hook sent wide of the posts. His miss didn't prove immediately costly as former All Black flanker Collins soon powered in for the first try, a positive decision to go to the corner rewarded by a powerful maul and Collins' finish.

The home side were let off the hook by two penalty misses from Sexton and the Leinster fly-half's evening took a further turn for the worse when his sharp break was ended by a crunching tackle from Byrne.

The hosts lost Collins to the sin-bin after he over-reacted to a shove from Sean O'Brien and Leinster opted to keep the pressure on with a scrum metres from the Ospreys line. Jones was repeatedly penalised for not binding, eventually seeing yellow and reducing the Ospreys to 13.

Leinster should have been awarded a penalty try at the same moment, but the referee's leniency cost them as from the next scrum the Ospreys won a penalty with only six men packing down.

After the resumption, Sexton and Hook traded penalties before Collins and Jones returned to the fray. Attacking opportunities were at a premium as both defences stood firm, Leinster ending the Ospreys' most potent attack with a nifty turnover following multiple phases of stout defence.

Ospreys boss Scott Johnson, already under pressure, unloaded his bench as the hour mark approached with Lions Mike Phillips, Alun-Wyn Jones and Shane Williams trotting on
to the field.

It was Leinster who produced the better play with ball in hand however, replacement centre
Fergus McFadden latching on to a pass from Wright and straightening his way to the line. Hauled down just short, McFadden recycled the ball and allowed Isa Nacewa to slot over a drop-goal.

With a one-point lead Leinster returned to their kicking strategy, while the Ospreys wasted two opportunities, once from a break by Dan Biggar and the second with knock on by an over-eager Byrne. Sexton punished their mistakes with another penalty, opening up a four point lead as the clock ticked past 70 minutes.

His final penalty secured the points, sending a small Ospreys crowd streaming for the exits and heaping further pressure on the coaching staff.